The invention relates to a fuel distributor housing and, more particularly, to a fuel distributor housing for an internal-combustion engine having a V-shaped cylinder arrangement, a forward flow device for the feeding and a return flow device for the removal of fuel and having receiving devices for injection valves. The fuel distributor housing extends along the internal-combustion engine which has an air collector in which first and second sections of suction pipes having throttling elements are arranged. The suction pipes carry an air current from the air collector to the intake ducts in the cylinder head of the internal-combustion engine, with injection valves assigned to the two sections of the suction pipes.
U.S. Pat. No. 4,576,131 shows an intake system for an air-fuel mixture of an internal-combustion engine which has two inlet valves for each cylinder. In this case, one intake pipe respectively leads from an air collector to each cylinder. Directly before entering the cylinder head, each intake pipe is divided into two sections which extend in parallel and lead to the two intake valves of each cylinder. A throttle valve is arranged in one or in both sections, respectively. A fuel line which extends along the internal-combustion engine is arranged on the outside and separately from the air collector. An injection valve for each cylinder is arranged at the fuel line which leads into the intake pipe in front of the division into the two sections.
In the EP-0102169, an intake system for an air-fuel mixture of an internal-combustion engine is shown in which a cast profile is arranged in the V-portion of crossing intake pipes. Lines extend inside this profile for the feeding and removal of fuel to individual injection valves which are assigned to the cylinders of the internal-combustion engine. The profile is screwed to the intake pipes as a separate component.
It is an object of the present invention to provide a compact fuel distributor housing which optimally utilizes the available space, can be manufactured easily and at low cost and permits a time-saving and cost-saving mounting.
This object has been achieved by a fuel distributor housing which forms a bottom part for an air collector and has second sections of the suction pipes constructed as ducts which are arranged between the top side and the bottom side of the fuel distributor housing transversely with respect to the forward flow device and to the return flow device 16 and can be blocked off by throttling elements. The ducts, combined in parallel extending rows, form the outer longitudinally extending boundaries of the fuel distributor housing; and the forward flow device, the return flow device and the receiving devices are arranged parallel between rows in which the ducts are combined.
In particular, the fuel distributor housing according to the present invention is constructed as the bottom part of an air collector and advantageously integrates sections extending in the form of ducts of the suction pipes extending to the intake ducts arranged in the cylinder head, throttle elements for the blocking of these ducts, all lines required for the feeding and the removal of fuel as well as receiving devices for injection valves which can be inserted into the fuel distributor housing.
The fuel distributor housing of the present invention has a compact shape and is arranged particularly advantageously in the space existing in the V portion of an internal-combustion engine with a V-shaped cylinder arrangement. The ducts which extend perpendicularly between the top side facing the top part of the air collector and the bottom side of the fuel distributor housing are combined in two rows which form the outer boundaries of the fuel distributor housing extending in the longitudinal course. A forward flow device used for the supply of fuel extends in the center between the rows and in parallel to them adjacent to the bottom side. One return flow device respectively for the removal of fuel extends on both sides at the same distance from the forward flow device and adjacent to the top side and is assigned to one row respectively.
The forward flow device and the return flow device are each connected with one another by way of a plane rib into which the receiving devices for the injection valves are integrated. The fuel distributor housing therefore has a V-shaped cross-section between the perpendicular rows of the ducts, and optimally utilizes the space existing between the rows.
The V-shaped design and an additional ribbing mounted on the top side and the bottom side renders the fuel distributor housing insensitive to the thermally caused mechanical tensions in the V-portion of the internal-combustion engine.
The integration of the injection valves operating at a high frequency in a central area of a rigid housing markedly reduces the sound radiation.
According to another aspect of the present invention, the two rows are longitudinally offset with respect to one another corresponding to the offsetting of the two cylinder banks of an internal-combustion V-engine. The area created by the longitudinal offsetting, on one end of the fuel distributor housing, is utilized by a holding device for a fuel pressure regulator.
The fuel distributor housing is cooled by the fuel amount which flows twice along its longitudinal course through the forward flow device and the return flow device. The fuel distributor housing according to the present invention makes superfluous the separate components which are normally used for the supply and the removal of fuel as well as their fastening elements. In addition, the fuel distributor housing can be mass produced in one machinable piece as a lightweight, sand-cast or diecast part made of aluminum which is easy to mount. Before the mounting, the fuel distributor housing may be subjected to a leak test while it is completely equipped. Expenditures are therefore avoided from the start which normally occur during the touch-up as a result of dismounting and mounting.
For a further weight reduction or when fuel qualities such as to be harmful to aluminum, the entire fuel distributor housing may also be manufactured of plastic.